Purcells

Slab avalanches continue to be reactive to human triggers at higher elevations. Danger will increase as a storm hits the region on Sunday night.

Moderate - Forecast snowfall amounts are uncertain

A low pressure system passing through the region on Sunday night will bring snow, but the amounts are fairly uncertain and could be highly variable.SUNDAY: Cloudy then flurries bring 2-5 cm of snow by the afternoon then intensifying in the evening with another 10-20 cm possibly overnight, moderate southwest wind, freezing level up to 1200 m, and alpine high temperatures near -6 C.MONDAY: Flurries continue into the morning then ease off in the afternoon, light wind, freezing level up to 900 m, and alpine high temperatures near -8 C.TUESDAY: Mix of sun and cloud, light wind, freezing level up to 1300 m, and alpine high temperatures near -5 C.

On Saturday a skier triggered a large slab avalanche (size 2.5) on a south aspect at 2600 m. The avalanche failed on a buried sun crust 150-200 cm below the surface.Several size 1-2 natural wind slabs and storm slabs were reported on a range of aspects on Thursday and Friday. A few size 1 skier triggered slabs on were reported on south aspects around 2300 m, including one that partially buried a skier.On Wednesday, several skier triggered avalanches up to size 2.5 were reported from all aspects above 2000 m. These avalanches predominantly failed on the late-March interface, with crown depths from 20-50 cm deep and up to 100 cm in some areas.

Snowfall amounts have been variable over the past week, with areas just east of Kootenay Lake receiving up to 80 cm of snow and eastern parts of the region receiving only 20-40 cm. The storm snow sits on an interface buried in late-March that consist of crusts below 1900 m and on south aspects, and surface hoar on shaded aspects at higher elevations. Other slightly deeper surface hoar/facet layers have been reported on shaded aspects at higher elevations and may be found approximately 40-60 cm below the surface.Deeper persistent weak layers from mid-late February as well as January and December layers, are still being monitored by professional observers, but are generally considered dormant. Facets also linger at the base of the snowpack.